Nowadays, people are always attacked by various diseases like atherosclerosis, myocardial infarction, spina bifida, congenital heart disease and senile dementia. At the same time, these diseases are nearly all connected with folic acid which is one kind of vitamin B and is first extracted from the leaves of spinach. 

Folic acid is produced by the integration of pteridine, para aminobenzoic acid and glutamic acid. The two kinds of folic acid existing in nature are dihydrofolic acid and tetrahydrofolic acid. However, only tetrahydrofolic acid has the physiological functions inside the human body. Tetrahydrofolic acid is a kind of carrier of one carbon unit. One carbon unit means the perssad containing one carbon atom during the process of metabolism inside the human body, such as methyl and hydroxymethyl. These one-carbon units of tetrahydrofolic acid can engage in the synthesis and supersession of many compounds, such as the synthesis of deoxyribonucleic acid, hemoglobin, adrenaline and choline. Generally speaking, there are about 5 to 6 milligrams of folic acid existing inside the human body, and 50% of folic acid is stored in the human liver. The content of folic acid in the blood can be affected by the recent foods, and the content of it in the red blood cells is relatively stable, which can reflect the nutritional situation of folic acid inside the human body. If 140 milligrams of folic acid are contained in each one liter of red blood cells, the nutritional situation is moderate.

The lack of folic acid can cause anemia among pregnant women and the fetuses. The development of germ cells, active activities of metabolism and the synthesis of protein all need a lot of folic acid. If the inadequate folic acid is stored in the red blood cells inside the bodies of pregnant women, the abortion can be caused by the maldevelopment of placenta. The maldevelopment of placenta usually hurts nervous centralis. According to the medical research, the main problems caused by the malnutrition of women are the anencephaly of the fetuses and spina bifida and so on. In addition, anemia can also cause placental abruption, toxemia of pregnancy and other gestational diseases.

In fact, the sources for people to supplement folic acid are rather diverse, such as the animal livers, yeast, vegetables and fruits. People, especially pregnant women, should attention to the supplementation of folic acid so as to prevent various diseases and protect the physical health.